This invention relates, in general, to crossovers and, more particularly, to coplanar waveguide crossovers.
Several types of crossovers are known in the art, such as the Butler U.S. Pat. Nos. 3,104,363 and 3,095,549. The basic problem throughout these prior art patents is that the electrical (E) fields of the crossing conductors are in the same plane and overlap each other. This can cause a mismatch in the impedance of the circuit containing the crossover.
In Butler U.S. Pat. No. 3,104,363 the width of the conductors is varied to try to compensate for the change in impedance caused by the crossover area. However, the E fields of the two conductors remain in the same plane which presents the need for the physical variances. In Butler U.S. Pat. No. 3,095,549 a pair of dual conductors is used to create a short area therebetween through which the crossing conductor is placed. This device requires the use of three layers of substrate and still has the E fields running in the same plane.